This invention pertains generally to loose fill packing materials and, more particularly, to the packaging of loose fill packing materials in bags for use as cushions in shipping cartons and the like.
Loose fill packing materials are widely used in the protective packing of articles for shipment. They are commonly poured into a carton so as to surround and embrace the articles and thereby cushion them during shipment. Loose fill materials are fabricated of a variety of materials such as foamed plastics and, more recently, starch and other biodegradable materials.
One problem with loose fill materials is that they tend to spill both during packaging and also when the cartons are opened and the articles packed in them are removed. Being light in weight, the materials also have a tendency to fly about, and some of them exhibit a static cling which makes them particularly difficult to deal with.
U.S. Pat. Nos. 5,778,642, 5,782,061, 5,782,067 and 5,826,404 disclose manually operated machines for packaging loose fill packing materials in bags for use as cushions in shipping cartons. This solves the problems of spillage and static cling while retaining the advantages of loose fill materials. However, the cushions are formed individually, and the machines were intended for use at or near the locations where the cushions are used. That is a disadvantage for shippers who do not want to make their own cushions or to have the equipment for making the cushions in their facilities.
It is in general an object of the invention to provide a new and improved packing cushion and machine and method for making the same.
Another object of the invention is to provide a packing cushion, machine and method of the above character which eliminates the messiness, spillage and static cling which occur when articles are packed in loose fill materials.
These and other objects are achieved in accordance with the invention by providing a string of cushions formed by two superposed layers of flexible plastic film sealed together along transversely extending lines to form a series of closed chambers, loose fill packing material in the chambers, and perforations in the film between the chambers defining tear lines by -which the cushions can be separated. In certain disclosed embodiments, the string of cushions is made by positioning an elongated length of flexible plastic tubing about a chute, drawing a section of the tubing from the chute, introducing loose fill packing material through the chute into the section of the tubing which has been drawn from the chute, sealing the walls of the tubing together along a transversely extending seal line above the loose fill packing material to close the section and form a cushion, perforating the tubing along a transversely extending tear line above the cushion, and repeating the process to form successive cushions separated by tear lines.